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CVE-2016-1938
The s_mp_div function in lib/freebl/mpi/mpi.c in Mozilla Network Security Services (NSS) before 3.21, as used in Mozilla Firefox before…
- 6.5MediumCVSS base score
- 3.2%Exploitation in 30 daysEPSS · top 12% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
The s_mp_div function in lib/freebl/mpi/mpi.c in Mozilla Network Security Services (NSS) before 3.21, as used in Mozilla Firefox before 44.0, improperly divides numbers, which might make it easier for remote attackers to defeat cryptographic protection mechanisms by leveraging use of the (1) mp_div or (2) mp_exptmod function.
Timeline
ID reserved
By mozilla
- 11 days later
· 11 days later
Published
- 9 years later
· 9 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| NVDNVD · Modified | 3.0 | Medium6.5 | CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N |
- EPSS (exploitation in 30 days)
- 3.2% · top 12% of all CVEs (9 Nov 2026)
Loading the EPSS history…
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 6.5.
Affected products
n/a
- affected n/a
References
23
- 81955 (opens in a new tab)vdb-entryx_refsource_BIDx_transferred
- DSA-3688 (opens in a new tab)vendor-advisoryx_refsource_DEBIANx_transferred
- 1034825 (opens in a new tab)vdb-entryx_refsource_SECTRACKx_transferred
- GLSA-201701-46 (opens in a new tab)vendor-advisoryx_refsource_GENTOOx_transferred
- http://www.oracle.com/technetwork/security-advisory/cpujul2016-2881720.html (opens in a new tab)x_refsource_CONFIRMx_transferred
- USN-2903-2 (opens in a new tab)vendor-advisoryx_refsource_UBUNTUx_transferred
- USN-2880-1 (opens in a new tab)vendor-advisoryx_refsource_UBUNTUx_transferred
- USN-2903-1 (opens in a new tab)vendor-advisoryx_refsource_UBUNTUx_transferred
- USN-2880-2 (opens in a new tab)vendor-advisoryx_refsource_UBUNTUx_transferred
- https://github.com/hannob/bignum-fuzz/blob/master/CVE-2016-1938-nss-mp_exptmod.c (opens in a new tab)x_refsource_MISCx_transferred
- https://developer.mozilla.org/en-US/docs/Mozilla/Projects/NSS/NSS_3.21_release_notes (opens in a new tab)x_refsource_MISCx_transferred
- SUSE-SU-2016:0338 (opens in a new tab)vendor-advisoryx_refsource_SUSEx_transferred
- http://www.mozilla.org/security/announce/2016/mfsa2016-07.html (opens in a new tab)x_refsource_CONFIRMx_transferred
- https://blog.fuzzing-project.org/37-Mozilla-NSS-Wrong-calculation-results-in-mp_div-and-mp_exptmod.html (opens in a new tab)x_refsource_MISCx_transferred
- USN-2973-1 (opens in a new tab)vendor-advisoryx_refsource_UBUNTUx_transferred
- https://bugzilla.mozilla.org/show_bug.cgi?id=1194947 (opens in a new tab)x_refsource_CONFIRMx_transferred
- openSUSE-SU-2016:0309 (opens in a new tab)vendor-advisoryx_refsource_SUSEx_transferred
- 91787 (opens in a new tab)vdb-entryx_refsource_BIDx_transferred
- https://github.com/hannob/bignum-fuzz/blob/master/CVE-2016-1938-nss-mp_div.c (opens in a new tab)x_refsource_MISCx_transferred
- GLSA-201605-06 (opens in a new tab)vendor-advisoryx_refsource_GENTOOx_transferred
- https://bugzilla.mozilla.org/show_bug.cgi?id=1190248 (opens in a new tab)x_refsource_CONFIRMx_transferred
- openSUSE-SU-2016:0306 (opens in a new tab)vendor-advisoryx_refsource_SUSEx_transferred
- https://hg.mozilla.org/projects/nss/diff/a555bf0fc23a/lib/freebl/mpi/mpi.c (opens in a new tab)x_refsource_CONFIRMx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2016-3027 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2016-1938)Record last updated .